1. Field of Invention
The present invention relates to turtle exclusion marine systems used, for example, during trawling operations, and more particularly a new and unique weedless, turtle exclusion device (TED) designed to exclude turtles and similarly sized animals and things from trawl nets and the like in an underwater environment, while allowing the desired catch therethrough.
The improvement relates to a new and unique weedless design and operation, which not only prevents seaweed build up and clogging about the deflection area, but also prevents clogging due to the accumulation of, for example, plastic bags and comparable undesirable refuse about the deflector as well.
The present system as disclosed in the preferred exemplary embodiment comprises an inexpensive yet effective weedless, turtle exclusion, marine system, which effectively releases turtles and the like from the trawl, yet does not substantially decrease the yield of shrimp or other harvest. Further, the present system provides a turtle exclusion system which reduces the labor required in the trawling process, as the operator no longer needs to raise the trawl to remove weeds and other debris from the deflector panel as often, if at all, as the system is designed to effectively remove such debris.
2. Prior Art & General Background
As may be determined by a review of the below cited patents, the prior art has failed to teach an effective "weedless" turtle exclusion device.
The prior art teaches various devices designed for releasing a variety of marine life and things from a multitude of nets. A list of prior patents which may be of interest is presented below:
______________________________________ Patent No. Patentee(s) Issue Date ______________________________________ 1,447,553 Hudson 03/06/1923 1,462,196 Dros 07/17/1923 1,745,251 Enright 01/28/1930 2,056,772 Dahl 02/02/1934 2,511,057 Guthrie et al 06/13/1950 2,721,411 Pedersen 10/25/1955 2,890,543 Mitchell 06/16/1959 3,015,903 Willingham 01/09/1962 3,132,434 Luketa 05/12/1964 3,195,261 Luketa 07/20/1965 3,440,752 Minter 04/29/1969 3,849,927 Gonsalves 11/26/1974 4,006,549 Seabrooke 02/08/1977 4,043,068 Savoie 08/23/1977 4,174,582 McKnight 11/20/1979 4,193,219 Pogue 03/18/1980 4,351,127 Mitchell 09/28/1982 4,402,154 Pence 09/06/1983 4,611,424 Tarantino 09/16/1986 4,739,574 Saunders 04/26/1988 4,805,335 West et al 02/21/1989 ______________________________________
As may be determined by a review of the above patents, the idea or concept regarding the "weedless" approach of turtle exclusion has not been expressed or otherwise taught in the prior art.
For example, U.S. Pat. No. 4,402,154 issued 1983 teaches a "Method and Apparatus for Classifying Marine Items" and teaches a device and method for separating shrimp and the like from trash and larger marine life, such as fish, turtles, etc. The device contemplates a baffle system including a plurality of parallel bars forming a deflection surface for deflecting larger marine life out of the path of the trawl net. It is noted that the parallel bars (11) are joined to the frame on one side (down-stream) but left in an "exposed" fashion on the "upstream" end.
The configuration as disclosed in the '154 patent is not weedless and would not function as disclosed in the present invention. The deflection bar design is opposite that contemplated by the present invention, which teaches bars joined on the upstream side of the frame and unjoined relative to the downstream side of the frame. Further, the present invention contemplates angled deflection bars relative to the deflection frame, thereby encouraging seaweed and the like to slide down and off the bars into the trap area, thereby preventing clogging of the TED.
U.S. Pat. No. 4,739,574 issued 1988 to Saunders of Biloxi, Miss. teaches a TED comprising a plurality of framed deflector bars joined on both ends by a deflector frame and perpendicular harness system.
Again, this patent is distinguishable from the present invention, as the claims relate to the overall structure of the device, including a net support member perpendicularly affixed to the barrier frame system, and a first and second horizontal bracing member with hinge means. As configured and used, the '574 invention is not weedless as taught in the present invention.
U.S. Pat. No. 4,805,335 issued Feb. 21, 1989 entitled "Sorting Device for Trawl Nets" teaches a trawl system having a deflector gate mechanism for allowing larger, heavier marine life, such as crabs and the like, to escape, thereby increasing the yield of desirable catch in the trawl. Like the above prior art, this patent does not contemplate a weedless system and is distinguishable again in operation and use.
The marine environment where trawlers operate tends to be replete with seaweed, moss, marine plants, as well as plastic ice bags, plastic garbage bags and the like. With the prior art exclusion devices, a persistent problem related to the collection of these plants and plastic bags on the deflection surface of the excluder, blocking it and preventing passage of the desired catch.
This blockage problem required the laborious and frequent task of raising the exclusion device to remove the debris from the deflection surface, interrupting the trawl and resulting in increased effort and expenses in the trawling operation.
As a result of this and other factors, the commercial fishing industry has tended to be vehemently opposed to legislation requiring the implementation of turtle exclusion devices, arguing that such devices severely hinder their fishing operations and the devices are ineffective in providing unencumbering exclusion means.
3. General, Summary Discussion of the Invention
The present invention provides a weedless, turtle exclusion system overcoming these prior art problems by providing a system which is highly reliable, relatively economical and very cost effective.
Unlike the prior art, the present system is at least substantially non-clogging, allowing passage of marine vegetation, plastic bags and the like through the deflection area and into the tail bag or codend, where it can be removed and disposed of properly.
Thus, the present invention provides a weedless, turtle exclusion device which does not require the periodic removal of blocking materials, while providing effective turtle exclusion means. This system as disclosed is superior over the prior art teachings in that it is practical for use by small and large scale fishing operations alike, allowing the user to comply with federal legislation regarding turtle exclusion, while not interfering with his catch.
The present system as disclosed in the exemplary embodiment of the invention comprises a framed set of angled deflection bars in parallel relation to one another, of sufficient width and having a surface which encourages the sliding of the vegetation, plastic, or the like down the bars during the trawling operation and into the tail bag or codend. The bars are angled in downstream fashion relative to the trawl, and are unconnected on their downstream ends, allowing the debris to pass down the bars due to the water current passing therethrough, over and off the bars, effectively preventing clogging of the system.
The exemplary system is comprised of aluminum, but many different materials may be used to form the present system. For example, the deflection bars may be "TEFLON" (tm) coated to insure a sufficiently slick, friction eliminating surface to allow the clogging matter to easily slide down the bars.
Further, the deflection system itself may be constructed from various materials in a variety of acceptable configurations including artificial materials, such as, for example, plastics or carbon fiber material, and/or a metal, such as, for example, steel, aluminum, stainless steel, and/or any and all manmade materials.
It is thus an object of the present invention to provide a weedless exclusion system for excluding turtles and like marine life from a trawl.
It is another object of the present invention to provide a turtle exclusion device which is economical to make and practical to use, without effecting the size of the user's catch.
It is still another object of the present invention to provide a turtle exclusion device comprising a partially framed set of angled deflection bars, configured to allow the passage of catch, seaweed, marine plants and plastic bags therethrough.
It is still another object of the present invention to provide a substantially weedless and non-clogging turtle exclusion device which may be adapted for use with a variety of trawl net sizes and configurations.
It is still another object of the present invention to provide a turtle exclusion device which is economical to manufacture and use, and which may be constructed utilizing relatively inexpensive materials.
Lastly, it is an object of the present invention to provide a substantially weedless and non-clogging method of excluding turtles and the like from the tail bag or codend, allowing escape of the turtles from the trawl.